Reinjection control in a geothermal power plant

The paper deals with the integrated process and control design verification of the re-injection section of a new-type geothermal power plant. The study is based on nonlinear dynamic simulation of the plant, including pressure wave propagation effects, while adopting a modular approach to process modelling. Besides the full-range plant simulator, linearized models are used for the control design. Due to a special approach to model discretization reasonably simple design models are obtained, which represent the relevant pressure wave dynamics. Both well-designed PI control and model-based digital control meet the operating requirements in normal and disturbed conditions.